The valve actuating mechanisms of motors having overhead cam shafts often include valve adjusting discs retained by disc receiving cam followers. The valve adjusting discs are maintained in abutting contact with the motor cam shaft by the cam follower. The effective clearance between the cam follower and the cam shaft (and therefore between the respective valve and valve seat) can be adjusted by varying the width of the valve adjusting disc. Manufacturer specifications for motor valve clearances require precise measurements and close tolerances. The width of valve pad adjusting discs in an overhead cam motor must accordingly be maintained within tolerances of one-half thousandths of an inch or less.